source3/lib/ctdbd_conn.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba internal messaging functions
   4    Copyright (C) 2007 by Volker Lendecke
   5    Copyright (C) 2007 by Andrew Tridgell
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22
  23 #ifdef CLUSTER_SUPPORT
  24
  25 #include "librpc/gen_ndr/messaging.h"
  26 #include "librpc/gen_ndr/ndr_messaging.h"
  27
  28 /* paths to these include files come from --with-ctdb= in configure */
  29 #include "ctdb.h"
  30 #include "ctdb_private.h"
  31
  32 struct ctdbd_connection {
  33         struct messaging_context *msg_ctx;
  34         uint32 reqid;
  35         uint32 our_vnn;
  36         uint64 rand_srvid;
  37         struct packet_context *pkt;
  38         struct fd_event *fde;
  39
  40         void (*release_ip_handler)(const char *ip_addr, void *private_data);
  41         void *release_ip_priv;
  42 };
  43
  44 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
  45                               uint32_t vnn, uint32 opcode,
  46                               uint64_t srvid, TDB_DATA data,
  47                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
  48                               int *cstatus);
  49
  50 /*
  51  * exit on fatal communications errors with the ctdbd daemon
  52  */
  53 static void cluster_fatal(const char *why)
  54 {
  55         DEBUG(0,("cluster fatal event: %s - exiting immediately\n", why));
  56         /* we don't use smb_panic() as we don't want to delay to write
  57            a core file. We need to release this process id immediately
  58            so that someone else can take over without getting sharing
  59            violations */
  60         _exit(0);
  61 }
  62
  63 /*
  64  *
  65  */
  66 static void ctdb_packet_dump(struct ctdb_req_header *hdr)
  67 {
  68         if (DEBUGLEVEL < 10) {
  69                 return;
  70         }
  71         DEBUGADD(10, ("len=%d, magic=%x, vers=%d, gen=%d, op=%d, reqid=%d\n",
  72                       (int)hdr->length, (int)hdr->ctdb_magic,
  73                       (int)hdr->ctdb_version, (int)hdr->generation,
  74                       (int)hdr->operation, (int)hdr->reqid));
  75 }
  76
  77 /*
  78  * Register a srvid with ctdbd
  79  */
  80 static NTSTATUS register_with_ctdbd(struct ctdbd_connection *conn,
  81                                     uint64_t srvid)
  82 {
  83
  84         int cstatus;
  85         return ctdbd_control(conn, CTDB_CURRENT_NODE,
  86                              CTDB_CONTROL_REGISTER_SRVID, srvid,
  87                              tdb_null, NULL, NULL, &cstatus);
  88 }
  89
  90 /*
  91  * get our vnn from the cluster
  92  */
  93 static NTSTATUS get_cluster_vnn(struct ctdbd_connection *conn, uint32 *vnn)
  94 {
  95         int32_t cstatus=-1;
  96         NTSTATUS status;
  97         status = ctdbd_control(conn,
  98                                CTDB_CURRENT_NODE, CTDB_CONTROL_GET_PNN, 0,
  99                                tdb_null, NULL, NULL, &cstatus);
 100         if (!NT_STATUS_IS_OK(status)) {
 101                 cluster_fatal("ctdbd_control failed\n");
 102         }
 103         *vnn = (uint32_t)cstatus;
 104         return status;
 105 }
 106
 107 uint32 ctdbd_vnn(const struct ctdbd_connection *conn)
 108 {
 109         return conn->our_vnn;
 110 }
 111
 112 /*
 113  * Get us a ctdb connection
 114  */
 115
 116 static NTSTATUS ctdbd_connect(TALLOC_CTX *mem_ctx,
 117                               struct packet_context **presult)
 118 {
 119         struct packet_context *result;
 120         const char *sockname = lp_ctdbd_socket();
 121         struct sockaddr_un addr;
 122         int fd;
 123
 124         if (!sockname || !*sockname) {
 125                 sockname = CTDB_PATH;
 126         }
 127
 128         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 129         if (fd == -1) {
 130                 DEBUG(3, ("Could not create socket: %s\n", strerror(errno)));
 131                 return map_nt_error_from_unix(errno);
 132         }
 133
 134         ZERO_STRUCT(addr);
 135         addr.sun_family = AF_UNIX;
 136         strncpy(addr.sun_path, sockname, sizeof(addr.sun_path));
 137
 138         if (sys_connect(fd, (struct sockaddr *)&addr) == -1) {
 139                 DEBUG(0, ("connect(%s) failed: %s\n", sockname,
 140                           strerror(errno)));
 141                 close(fd);
 142                 return map_nt_error_from_unix(errno);
 143         }
 144
 145         if (!(result = packet_init(mem_ctx, fd))) {
 146                 close(fd);
 147                 return NT_STATUS_NO_MEMORY;
 148         }
 149
 150         *presult = result;
 151         return NT_STATUS_OK;
 152 }
 153
 154 /*
 155  * Do we have a complete ctdb packet in the queue?
 156  */
 157
 158 static bool ctdb_req_complete(const struct data_blob *data,
 159                               size_t *length,
 160                               void *private_data)
 161 {
 162         uint32 msglen;
 163
 164         if (data->length < sizeof(msglen)) {
 165                 return False;
 166         }
 167
 168         msglen = *((uint32 *)data->data);
 169
 170         DEBUG(10, ("msglen = %d\n", msglen));
 171
 172         if (msglen < sizeof(struct ctdb_req_header)) {
 173                 DEBUG(0, ("Got invalid msglen: %d, expected at least %d for "
 174                           "the req_header\n", (int)msglen,
 175                           (int)sizeof(struct ctdb_req_header)));
 176                 cluster_fatal("ctdbd protocol error\n");
 177         }
 178
 179         if (data->length >= msglen) {
 180                 *length = msglen;
 181                 return True;
 182         }
 183
 184         return False;
 185 }
 186
 187 /*
 188  * State necessary to defer an incoming message while we are waiting for a
 189  * ctdb reply.
 190  */
 191
 192 struct deferred_msg_state {
 193         struct messaging_context *msg_ctx;
 194         struct messaging_rec *rec;
 195 };
 196
 197 /*
 198  * Timed event handler for the deferred message
 199  */
 200
 201 static void deferred_message_dispatch(struct event_context *event_ctx,
 202                                       struct timed_event *te,
 203                                       const struct timeval *now,
 204                                       void *private_data)
 205 {
 206         struct deferred_msg_state *state = talloc_get_type_abort(
 207                 private_data, struct deferred_msg_state);
 208
 209         messaging_dispatch_rec(state->msg_ctx, state->rec);
 210         TALLOC_FREE(state);
 211         TALLOC_FREE(te);
 212 }
 213
 214 struct req_pull_state {
 215         TALLOC_CTX *mem_ctx;
 216         DATA_BLOB req;
 217 };
 218
 219 /*
 220  * Pull a ctdb request out of the incoming packet queue
 221  */
 222
 223 static NTSTATUS ctdb_req_pull(const struct data_blob *data,
 224                               void *private_data)
 225 {
 226         struct req_pull_state *state = (struct req_pull_state *)private_data;
 227
 228         state->req = data_blob_talloc(state->mem_ctx, data->data,
 229                                       data->length);
 230         if (state->req.data == NULL) {
 231                 return NT_STATUS_NO_MEMORY;
 232         }
 233         return NT_STATUS_OK;
 234 }
 235
 236 /*
 237  * Fetch a messaging_rec from an incoming ctdb style message
 238  */
 239
 240 static struct messaging_rec *ctdb_pull_messaging_rec(TALLOC_CTX *mem_ctx,
 241                                                      size_t overall_length,
 242                                                      struct ctdb_req_message *msg)
 243 {
 244         struct messaging_rec *result;
 245         DATA_BLOB blob;
 246         enum ndr_err_code ndr_err;
 247
 248         if ((overall_length < offsetof(struct ctdb_req_message, data))
 249             || (overall_length
 250                 < offsetof(struct ctdb_req_message, data) + msg->datalen)) {
 251
 252                 cluster_fatal("got invalid msg length");
 253         }
 254
 255         if (!(result = TALLOC_P(mem_ctx, struct messaging_rec))) {
 256                 DEBUG(0, ("talloc failed\n"));
 257                 return NULL;
 258         }
 259
 260         blob = data_blob_const(msg->data, msg->datalen);
 261
 262         ndr_err = ndr_pull_struct_blob(
 263                 &blob, result, result,
 264                 (ndr_pull_flags_fn_t)ndr_pull_messaging_rec);
 265
 266         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 267                 DEBUG(0, ("ndr_pull_struct_blob failed: %s\n",
 268                           ndr_errstr(ndr_err)));
 269                 TALLOC_FREE(result);
 270                 return NULL;
 271         }
 272
 273         if (DEBUGLEVEL >= 10) {
 274                 DEBUG(10, ("ctdb_pull_messaging_rec:\n"));
 275                 NDR_PRINT_DEBUG(messaging_rec, result);
 276         }
 277
 278         return result;
 279 }
 280
 281 /*
 282  * Read a full ctdbd request. If we have a messaging context, defer incoming
 283  * messages that might come in between.
 284  */
 285
 286 static NTSTATUS ctdb_read_req(struct ctdbd_connection *conn, uint32 reqid,
 287                               TALLOC_CTX *mem_ctx, void *result)
 288 {
 289         struct ctdb_req_header *hdr;
 290         struct req_pull_state state;
 291         NTSTATUS status;
 292
 293  again:
 294
 295         status = packet_fd_read_sync(conn->pkt);
 296
 297         if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_BUSY)) {
 298                 /* EAGAIN */
 299                 goto again;
 300         } else if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
 301                 /* EAGAIN */
 302                 goto again;
 303         }
 304
 305         if (!NT_STATUS_IS_OK(status)) {
 306                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 307                 cluster_fatal("ctdbd died\n");
 308         }
 309
 310  next_pkt:
 311
 312         ZERO_STRUCT(state);
 313         state.mem_ctx = mem_ctx;
 314
 315         if (!packet_handler(conn->pkt, ctdb_req_complete, ctdb_req_pull,
 316                             &state, &status)) {
 317                 /*
 318                  * Not enough data
 319                  */
 320                 DEBUG(10, ("not enough data from ctdb socket, retrying\n"));
 321                 goto again;
 322         }
 323
 324         if (!NT_STATUS_IS_OK(status)) {
 325                 DEBUG(0, ("Could not read packet: %s\n", nt_errstr(status)));
 326                 cluster_fatal("ctdbd died\n");
 327         }
 328
 329         hdr = (struct ctdb_req_header *)state.req.data;
 330
 331         DEBUG(10, ("Received ctdb packet\n"));
 332         ctdb_packet_dump(hdr);
 333
 334         if (hdr->operation == CTDB_REQ_MESSAGE) {
 335                 struct timed_event *evt;
 336                 struct deferred_msg_state *msg_state;
 337                 struct ctdb_req_message *msg = (struct ctdb_req_message *)hdr;
 338
 339                 if (conn->msg_ctx == NULL) {
 340                         DEBUG(1, ("Got a message without having a msg ctx, "
 341                                   "dropping msg %llu\n",
 342                                   (long long unsigned)msg->srvid));
 343                         goto next_pkt;
 344                 }
 345
 346                 if ((conn->release_ip_handler != NULL)
 347                     && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 348                         /* must be dispatched immediately */
 349                         DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 350                         conn->release_ip_handler((const char *)msg->data,
 351                                                  conn->release_ip_priv);
 352                         TALLOC_FREE(hdr);
 353                         goto next_pkt;
 354                 }
 355
 356                 if (!(msg_state = TALLOC_P(NULL, struct deferred_msg_state))) {
 357                         DEBUG(0, ("talloc failed\n"));
 358                         TALLOC_FREE(hdr);
 359                         goto next_pkt;
 360                 }
 361
 362                 if (!(msg_state->rec = ctdb_pull_messaging_rec(
 363                               msg_state, state.req.length, msg))) {
 364                         DEBUG(0, ("ctdbd_pull_messaging_rec failed\n"));
 365                         TALLOC_FREE(msg_state);
 366                         TALLOC_FREE(hdr);
 367                         goto next_pkt;
 368                 }
 369
 370                 TALLOC_FREE(hdr);
 371
 372                 msg_state->msg_ctx = conn->msg_ctx;
 373
 374                 /*
 375                  * We're waiting for a call reply, but an async message has
 376                  * crossed. Defer dispatching to the toplevel event loop.
 377                  */
 378                 evt = event_add_timed(conn->msg_ctx->event_ctx,
 379                                       conn->msg_ctx->event_ctx,
 380                                       timeval_zero(),
 381                                       "deferred_message_dispatch",
 382                                       deferred_message_dispatch,
 383                                       msg_state);
 384                 if (evt == NULL) {
 385                         DEBUG(0, ("event_add_timed failed\n"));
 386                         TALLOC_FREE(msg_state);
 387                         TALLOC_FREE(hdr);
 388                         goto next_pkt;
 389                 }
 390
 391                 goto next_pkt;
 392         }
 393
 394         if (hdr->reqid != reqid) {
 395                 /* we got the wrong reply */
 396                 DEBUG(0,("Discarding mismatched ctdb reqid %u should have "
 397                          "been %u\n", hdr->reqid, reqid));
 398                 TALLOC_FREE(hdr);
 399                 goto again;
 400         }
 401
 402         *((void **)result) = talloc_move(mem_ctx, &hdr);
 403
 404         return NT_STATUS_OK;
 405 }
 406
 407 /*
 408  * Get us a ctdbd connection
 409  */
 410
 411 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
 412                                struct ctdbd_connection **pconn)
 413 {
 414         struct ctdbd_connection *conn;
 415         NTSTATUS status;
 416
 417         if (!(conn = TALLOC_ZERO_P(mem_ctx, struct ctdbd_connection))) {
 418                 DEBUG(0, ("talloc failed\n"));
 419                 return NT_STATUS_NO_MEMORY;
 420         }
 421
 422         status = ctdbd_connect(conn, &conn->pkt);
 423
 424         if (!NT_STATUS_IS_OK(status)) {
 425                 DEBUG(10, ("ctdbd_connect failed: %s\n", nt_errstr(status)));
 426                 goto fail;
 427         }
 428
 429         status = get_cluster_vnn(conn, &conn->our_vnn);
 430
 431         if (!NT_STATUS_IS_OK(status)) {
 432                 DEBUG(10, ("get_cluster_vnn failed: %s\n", nt_errstr(status)));
 433                 goto fail;
 434         }
 435
 436         generate_random_buffer((unsigned char *)&conn->rand_srvid,
 437                                sizeof(conn->rand_srvid));
 438
 439         status = register_with_ctdbd(conn, conn->rand_srvid);
 440
 441         if (!NT_STATUS_IS_OK(status)) {
 442                 DEBUG(5, ("Could not register random srvid: %s\n",
 443                           nt_errstr(status)));
 444                 goto fail;
 445         }
 446
 447         *pconn = conn;
 448         return NT_STATUS_OK;
 449
 450  fail:
 451         TALLOC_FREE(conn);
 452         return status;
 453 }
 454
 455 /*
 456  * Get us a ctdbd connection and register us as a process
 457  */
 458
 459 NTSTATUS ctdbd_messaging_connection(TALLOC_CTX *mem_ctx,
 460                                     struct ctdbd_connection **pconn)
 461 {
 462         struct ctdbd_connection *conn;
 463         NTSTATUS status;
 464
 465         status = ctdbd_init_connection(mem_ctx, &conn);
 466
 467         if (!NT_STATUS_IS_OK(status)) {
 468                 return status;
 469         }
 470
 471         status = register_with_ctdbd(conn, (uint64_t)sys_getpid());
 472         if (!NT_STATUS_IS_OK(status)) {
 473                 goto fail;
 474         }
 475
 476         status = register_with_ctdbd(conn, MSG_SRVID_SAMBA);
 477         if (!NT_STATUS_IS_OK(status)) {
 478                 goto fail;
 479         }
 480
 481         *pconn = conn;
 482         return NT_STATUS_OK;
 483
 484  fail:
 485         TALLOC_FREE(conn);
 486         return status;
 487 }
 488
 489 /*
 490  * Packet handler to receive and handle a ctdb message
 491  */
 492 static NTSTATUS ctdb_handle_message(const struct data_blob *data,
 493                                     void *private_data)
 494 {
 495         struct ctdbd_connection *conn = talloc_get_type_abort(
 496                 private_data, struct ctdbd_connection);
 497         struct ctdb_req_message *msg;
 498         struct messaging_rec *msg_rec;
 499
 500         msg = (struct ctdb_req_message *)data->data;
 501
 502         if (msg->hdr.operation != CTDB_REQ_MESSAGE) {
 503                 DEBUG(0, ("Received async msg of type %u, discarding\n",
 504                           msg->hdr.operation));
 505                 return NT_STATUS_INVALID_PARAMETER;
 506         }
 507
 508         if ((conn->release_ip_handler != NULL)
 509             && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 510                 /* must be dispatched immediately */
 511                 DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 512                 conn->release_ip_handler((const char *)msg->data,
 513                                          conn->release_ip_priv);
 514                 return NT_STATUS_OK;
 515         }
 516
 517         SMB_ASSERT(conn->msg_ctx != NULL);
 518
 519         if (msg->srvid == CTDB_SRVID_RECONFIGURE) {
 520                 DEBUG(0,("Got cluster reconfigure message\n"));
 521                 /*
 522                  * when the cluster is reconfigured, we need to clean the brl
 523                  * database
 524                  */
 525                 messaging_send(conn->msg_ctx, procid_self(),
 526                                MSG_SMB_BRL_VALIDATE, &data_blob_null);
 527
 528                 /*
 529                  * it's possible that we have just rejoined the cluster after
 530                  * an outage. In that case our pending locks could have been
 531                  * removed from the lockdb, so retry them once more
 532                  */
 533                 message_send_all(conn->msg_ctx, MSG_SMB_UNLOCK, NULL, 0, NULL);
 534
 535                 return NT_STATUS_OK;
 536
 537         }
 538
 539         /* only messages to our pid or the broadcast are valid here */
 540         if (msg->srvid != sys_getpid() && msg->srvid != MSG_SRVID_SAMBA) {
 541                 DEBUG(0,("Got unexpected message with srvid=%llu\n",
 542                          (unsigned long long)msg->srvid));
 543                 return NT_STATUS_OK;
 544         }
 545
 546         if (!(msg_rec = ctdb_pull_messaging_rec(NULL, data->length, msg))) {
 547                 DEBUG(10, ("ctdb_pull_messaging_rec failed\n"));
 548                 return NT_STATUS_NO_MEMORY;
 549         }
 550
 551         messaging_dispatch_rec(conn->msg_ctx, msg_rec);
 552
 553         TALLOC_FREE(msg_rec);
 554         return NT_STATUS_OK;
 555 }
 556
 557 /*
 558  * The ctdbd socket is readable asynchronuously
 559  */
 560
 561 static void ctdbd_socket_handler(struct event_context *event_ctx,
 562                                  struct fd_event *event,
 563                                  uint16 flags,
 564                                  void *private_data)
 565 {
 566         struct ctdbd_connection *conn = talloc_get_type_abort(
 567                 private_data, struct ctdbd_connection);
 568
 569         NTSTATUS status;
 570
 571         status = packet_fd_read(conn->pkt);
 572
 573         if (!NT_STATUS_IS_OK(status)) {
 574                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 575                 cluster_fatal("ctdbd died\n");
 576         }
 577
 578         while (packet_handler(conn->pkt, ctdb_req_complete,
 579                               ctdb_handle_message, conn, &status)) {
 580                 if (!NT_STATUS_IS_OK(status)) {
 581                         DEBUG(10, ("could not handle incoming message: %s\n",
 582                                    nt_errstr(status)));
 583                 }
 584         }
 585 }
 586
 587 /*
 588  * Prepare a ctdbd connection to receive messages
 589  */
 590
 591 NTSTATUS ctdbd_register_msg_ctx(struct ctdbd_connection *conn,
 592                                 struct messaging_context *msg_ctx)
 593 {
 594         SMB_ASSERT(conn->msg_ctx == NULL);
 595         SMB_ASSERT(conn->fde == NULL);
 596
 597         if (!(conn->fde = event_add_fd(msg_ctx->event_ctx, conn,
 598                                        packet_get_fd(conn->pkt),
 599                                        EVENT_FD_READ,
 600                                        ctdbd_socket_handler,
 601                                        conn))) {
 602                 DEBUG(0, ("event_add_fd failed\n"));
 603                 return NT_STATUS_NO_MEMORY;
 604         }
 605
 606         conn->msg_ctx = msg_ctx;
 607
 608         return NT_STATUS_OK;
 609 }
 610
 611 /*
 612  * Send a messaging message across a ctdbd
 613  */
 614
 615 NTSTATUS ctdbd_messaging_send(struct ctdbd_connection *conn,
 616                               uint32 dst_vnn, uint64 dst_srvid,
 617                               struct messaging_rec *msg)
 618 {
 619         struct ctdb_req_message r;
 620         TALLOC_CTX *mem_ctx;
 621         DATA_BLOB blob;
 622         NTSTATUS status;
 623         enum ndr_err_code ndr_err;
 624
 625         if (!(mem_ctx = talloc_init("ctdbd_messaging_send"))) {
 626                 DEBUG(0, ("talloc failed\n"));
 627                 return NT_STATUS_NO_MEMORY;
 628         }
 629
 630         ndr_err = ndr_push_struct_blob(
 631                 &blob, mem_ctx, msg,
 632                 (ndr_push_flags_fn_t)ndr_push_messaging_rec);
 633
 634         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 635                 DEBUG(0, ("ndr_push_struct_blob failed: %s\n",
 636                           ndr_errstr(ndr_err)));
 637                 status = ndr_map_error2ntstatus(ndr_err);
 638                 goto fail;
 639         }
 640
 641         r.hdr.length = offsetof(struct ctdb_req_message, data) + blob.length;
 642         r.hdr.ctdb_magic = CTDB_MAGIC;
 643         r.hdr.ctdb_version = CTDB_VERSION;
 644         r.hdr.generation = 1;
 645         r.hdr.operation  = CTDB_REQ_MESSAGE;
 646         r.hdr.destnode   = dst_vnn;
 647         r.hdr.srcnode    = conn->our_vnn;
 648         r.hdr.reqid      = 0;
 649         r.srvid          = dst_srvid;
 650         r.datalen        = blob.length;
 651
 652         DEBUG(10, ("ctdbd_messaging_send: Sending ctdb packet\n"));
 653         ctdb_packet_dump(&r.hdr);
 654
 655         status = packet_send(
 656                 conn->pkt, 2,
 657                 data_blob_const(&r, offsetof(struct ctdb_req_message, data)),
 658                 blob);
 659
 660         if (!NT_STATUS_IS_OK(status)) {
 661                 DEBUG(0, ("packet_send failed: %s\n", nt_errstr(status)));
 662                 goto fail;
 663         }
 664
 665         status = packet_flush(conn->pkt);
 666
 667         if (!NT_STATUS_IS_OK(status)) {
 668                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 669                 cluster_fatal("cluster dispatch daemon msg write error\n");
 670         }
 671
 672         status = NT_STATUS_OK;
 673  fail:
 674         TALLOC_FREE(mem_ctx);
 675         return status;
 676 }
 677
 678 /*
 679  * send/recv a generic ctdb control message
 680  */
 681 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
 682                               uint32_t vnn, uint32 opcode,
 683                               uint64_t srvid, TDB_DATA data,
 684                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
 685                               int *cstatus)
 686 {
 687         struct ctdb_req_control req;
 688         struct ctdb_reply_control *reply = NULL;
 689         struct ctdbd_connection *new_conn = NULL;
 690         NTSTATUS status;
 691
 692         if (conn == NULL) {
 693                 status = ctdbd_init_connection(NULL, &new_conn);
 694
 695                 if (!NT_STATUS_IS_OK(status)) {
 696                         DEBUG(10, ("Could not init temp connection: %s\n",
 697                                    nt_errstr(status)));
 698                         goto fail;
 699                 }
 700
 701                 conn = new_conn;
 702         }
 703
 704         ZERO_STRUCT(req);
 705         req.hdr.length = offsetof(struct ctdb_req_control, data) + data.dsize;
 706         req.hdr.ctdb_magic   = CTDB_MAGIC;
 707         req.hdr.ctdb_version = CTDB_VERSION;
 708         req.hdr.operation    = CTDB_REQ_CONTROL;
 709         req.hdr.reqid        = ++conn->reqid;
 710         req.hdr.destnode     = vnn;
 711         req.opcode           = opcode;
 712         req.srvid            = srvid;
 713         req.datalen          = data.dsize;
 714
 715         DEBUG(10, ("ctdbd_control: Sending ctdb packet\n"));
 716         ctdb_packet_dump(&req.hdr);
 717
 718         status = packet_send(
 719                 conn->pkt, 2,
 720                 data_blob_const(&req, offsetof(struct ctdb_req_control, data)),
 721                 data_blob_const(data.dptr, data.dsize));
 722
 723         if (!NT_STATUS_IS_OK(status)) {
 724                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 725                 goto fail;
 726         }
 727
 728         status = packet_flush(conn->pkt);
 729
 730         if (!NT_STATUS_IS_OK(status)) {
 731                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 732                 cluster_fatal("cluster dispatch daemon control write error\n");
 733         }
 734
 735         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 736
 737         if (!NT_STATUS_IS_OK(status)) {
 738                 DEBUG(10, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 739                 goto fail;
 740         }
 741
 742         if (reply->hdr.operation != CTDB_REPLY_CONTROL) {
 743                 DEBUG(0, ("received invalid reply\n"));
 744                 goto fail;
 745         }
 746
 747         if (outdata) {
 748                 if (!(outdata->dptr = (uint8 *)talloc_memdup(
 749                               mem_ctx, reply->data, reply->datalen))) {
 750                         TALLOC_FREE(reply);
 751                         return NT_STATUS_NO_MEMORY;
 752                 }
 753                 outdata->dsize = reply->datalen;
 754         }
 755         if (cstatus) {
 756                 (*cstatus) = reply->status;
 757         }
 758
 759         status = NT_STATUS_OK;
 760
 761  fail:
 762         TALLOC_FREE(new_conn);
 763         TALLOC_FREE(reply);
 764         return status;
 765 }
 766
 767 /*
 768  * see if a remote process exists
 769  */
 770 bool ctdbd_process_exists(struct ctdbd_connection *conn, uint32 vnn, pid_t pid)
 771 {
 772         NTSTATUS status;
 773         TDB_DATA data;
 774         int32_t cstatus;
 775
 776         data.dptr = (uint8_t*)&pid;
 777         data.dsize = sizeof(pid);
 778
 779         status = ctdbd_control(conn, vnn, CTDB_CONTROL_PROCESS_EXISTS, 0,
 780                                data, NULL, NULL, &cstatus);
 781         if (!NT_STATUS_IS_OK(status)) {
 782                 DEBUG(0, (__location__ " ctdb_control for process_exists "
 783                           "failed\n"));
 784                 return False;
 785         }
 786
 787         return cstatus == 0;
 788 }
 789
 790 /*
 791  * Get a db path
 792  */
 793 char *ctdbd_dbpath(struct ctdbd_connection *conn,
 794                    TALLOC_CTX *mem_ctx, uint32_t db_id)
 795 {
 796         NTSTATUS status;
 797         TDB_DATA data;
 798         int32_t cstatus;
 799
 800         data.dptr = (uint8_t*)&db_id;
 801         data.dsize = sizeof(db_id);
 802
 803         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 804                                CTDB_CONTROL_GETDBPATH, 0, data,
 805                                mem_ctx, &data, &cstatus);
 806         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 807                 DEBUG(0,(__location__ " ctdb_control for getdbpath failed\n"));
 808                 return NULL;
 809         }
 810
 811         return (char *)data.dptr;
 812 }
 813
 814 /*
 815  * attach to a ctdb database
 816  */
 817 NTSTATUS ctdbd_db_attach(struct ctdbd_connection *conn,
 818                          const char *name, uint32_t *db_id, int tdb_flags)
 819 {
 820         NTSTATUS status;
 821         TDB_DATA data;
 822         int32_t cstatus;
 823
 824         data.dptr = (uint8_t*)name;
 825         data.dsize = strlen(name)+1;
 826
 827         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 828                                CTDB_CONTROL_DB_ATTACH, 0, data,
 829                                NULL, &data, &cstatus);
 830         if (!NT_STATUS_IS_OK(status)) {
 831                 DEBUG(0, (__location__ " ctdb_control for db_attach "
 832                           "failed: %s\n", nt_errstr(status)));
 833                 return status;
 834         }
 835
 836         if (cstatus != 0 || data.dsize != sizeof(uint32_t)) {
 837                 DEBUG(0,(__location__ " ctdb_control for db_attach failed\n"));
 838                 return NT_STATUS_INTERNAL_ERROR;
 839         }
 840
 841         *db_id = *(uint32_t *)data.dptr;
 842         talloc_free(data.dptr);
 843
 844         if (!(tdb_flags & TDB_SEQNUM)) {
 845                 return NT_STATUS_OK;
 846         }
 847
 848         data.dptr = (uint8_t *)db_id;
 849         data.dsize = sizeof(*db_id);
 850
 851         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 852                                CTDB_CONTROL_ENABLE_SEQNUM, 0, data,
 853                                NULL, NULL, &cstatus);
 854         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 855                 DEBUG(0,(__location__ " ctdb_control for enable seqnum "
 856                          "failed\n"));
 857                 return NT_STATUS_IS_OK(status) ? NT_STATUS_INTERNAL_ERROR :
 858                         status;
 859         }
 860
 861         return NT_STATUS_OK;
 862 }
 863
 864 /*
 865  * force the migration of a record to this node
 866  */
 867 NTSTATUS ctdbd_migrate(struct ctdbd_connection *conn, uint32 db_id,
 868                        TDB_DATA key)
 869 {
 870         struct ctdb_req_call req;
 871         struct ctdb_reply_call *reply;
 872         NTSTATUS status;
 873
 874         ZERO_STRUCT(req);
 875
 876         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 877         req.hdr.ctdb_magic   = CTDB_MAGIC;
 878         req.hdr.ctdb_version = CTDB_VERSION;
 879         req.hdr.operation    = CTDB_REQ_CALL;
 880         req.hdr.reqid        = ++conn->reqid;
 881         req.flags            = CTDB_IMMEDIATE_MIGRATION;
 882         req.callid           = CTDB_NULL_FUNC;
 883         req.db_id            = db_id;
 884         req.keylen           = key.dsize;
 885
 886         DEBUG(10, ("ctdbd_migrate: Sending ctdb packet\n"));
 887         ctdb_packet_dump(&req.hdr);
 888
 889         status = packet_send(
 890                 conn->pkt, 2,
 891                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 892                 data_blob_const(key.dptr, key.dsize));
 893
 894         if (!NT_STATUS_IS_OK(status)) {
 895                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 896                 return status;
 897         }
 898
 899         status = packet_flush(conn->pkt);
 900
 901         if (!NT_STATUS_IS_OK(status)) {
 902                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 903                 cluster_fatal("cluster dispatch daemon control write error\n");
 904         }
 905
 906         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 907
 908         if (!NT_STATUS_IS_OK(status)) {
 909                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 910                 goto fail;
 911         }
 912
 913         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 914                 DEBUG(0, ("received invalid reply\n"));
 915                 status = NT_STATUS_INTERNAL_ERROR;
 916                 goto fail;
 917         }
 918
 919         status = NT_STATUS_OK;
 920  fail:
 921
 922         TALLOC_FREE(reply);
 923         return status;
 924 }
 925
 926 /*
 927  * remotely fetch a record without locking it or forcing a migration
 928  */
 929 NTSTATUS ctdbd_fetch(struct ctdbd_connection *conn, uint32 db_id,
 930                      TDB_DATA key, TALLOC_CTX *mem_ctx, TDB_DATA *data)
 931 {
 932         struct ctdb_req_call req;
 933         struct ctdb_reply_call *reply;
 934         NTSTATUS status;
 935
 936         ZERO_STRUCT(req);
 937
 938         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 939         req.hdr.ctdb_magic   = CTDB_MAGIC;
 940         req.hdr.ctdb_version = CTDB_VERSION;
 941         req.hdr.operation    = CTDB_REQ_CALL;
 942         req.hdr.reqid        = ++conn->reqid;
 943         req.flags            = 0;
 944         req.callid           = CTDB_FETCH_FUNC;
 945         req.db_id            = db_id;
 946         req.keylen           = key.dsize;
 947
 948         status = packet_send(
 949                 conn->pkt, 2,
 950                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 951                 data_blob_const(key.dptr, key.dsize));
 952
 953         if (!NT_STATUS_IS_OK(status)) {
 954                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 955                 return status;
 956         }
 957
 958         status = packet_flush(conn->pkt);
 959
 960         if (!NT_STATUS_IS_OK(status)) {
 961                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 962                 cluster_fatal("cluster dispatch daemon control write error\n");
 963         }
 964
 965         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 966
 967         if (!NT_STATUS_IS_OK(status)) {
 968                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 969                 goto fail;
 970         }
 971
 972         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 973                 DEBUG(0, ("received invalid reply\n"));
 974                 status = NT_STATUS_INTERNAL_ERROR;
 975                 goto fail;
 976         }
 977
 978         data->dsize = reply->datalen;
 979         if (data->dsize == 0) {
 980                 data->dptr = NULL;
 981                 goto done;
 982         }
 983
 984         data->dptr = (uint8 *)talloc_memdup(mem_ctx, &reply->data[0],
 985                                             reply->datalen);
 986         if (data->dptr == NULL) {
 987                 DEBUG(0, ("talloc failed\n"));
 988                 status = NT_STATUS_NO_MEMORY;
 989                 goto fail;
 990         }
 991
 992  done:
 993         status = NT_STATUS_OK;
 994  fail:
 995         TALLOC_FREE(reply);
 996         return status;
 997 }
 998
 999 struct ctdbd_traverse_state {
1000         void (*fn)(TDB_DATA key, TDB_DATA data, void *private_data);
1001         void *private_data;
1002 };
1003
1004 /*
1005  * Handle a traverse record coming in on the ctdbd connection
1006  */
1007
1008 static NTSTATUS ctdb_traverse_handler(const struct data_blob *blob,
1009                                       void *private_data)
1010 {
1011         struct ctdbd_traverse_state *state =
1012                 (struct ctdbd_traverse_state *)private_data;
1013
1014         struct ctdb_req_message *m;
1015         struct ctdb_rec_data *d;
1016         TDB_DATA key, data;
1017
1018         m = (struct ctdb_req_message *)blob->data;
1019
1020         if (blob->length < sizeof(*m) || m->hdr.length != blob->length) {
1021                 DEBUG(0, ("Got invalid message of length %d\n",
1022                           (int)blob->length));
1023                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1024         }
1025
1026         d = (struct ctdb_rec_data *)&m->data[0];
1027         if (m->datalen < sizeof(uint32_t) || m->datalen != d->length) {
1028                 DEBUG(0, ("Got invalid traverse data of length %d\n",
1029                           (int)m->datalen));
1030                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1031         }
1032
1033         key.dsize = d->keylen;
1034         key.dptr  = &d->data[0];
1035         data.dsize = d->datalen;
1036         data.dptr = &d->data[d->keylen];
1037
1038         if (key.dsize == 0 && data.dsize == 0) {
1039                 /* end of traverse */
1040                 return NT_STATUS_END_OF_FILE;
1041         }
1042
1043         if (data.dsize < sizeof(struct ctdb_ltdb_header)) {
1044                 DEBUG(0, ("Got invalid ltdb header length %d\n",
1045                           (int)data.dsize));
1046                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1047         }
1048         data.dsize -= sizeof(struct ctdb_ltdb_header);
1049         data.dptr += sizeof(struct ctdb_ltdb_header);
1050
1051         if (state->fn) {
1052                 state->fn(key, data, state->private_data);
1053         }
1054
1055         return NT_STATUS_OK;
1056 }
1057
1058 /*
1059   Traverse a ctdb database. This uses a kind-of hackish way to open a second
1060   connection to ctdbd to avoid the hairy recursive and async problems with
1061   everything in-line.
1062 */
1063
1064 NTSTATUS ctdbd_traverse(uint32 db_id,
1065                         void (*fn)(TDB_DATA key, TDB_DATA data,
1066                                    void *private_data),
1067                         void *private_data)
1068 {
1069         struct ctdbd_connection *conn;
1070         NTSTATUS status;
1071
1072         TDB_DATA data;
1073         struct ctdb_traverse_start t;
1074         int cstatus;
1075         struct ctdbd_traverse_state state;
1076
1077         status = ctdbd_init_connection(NULL, &conn);
1078
1079         t.db_id = db_id;
1080         t.srvid = conn->rand_srvid;
1081         t.reqid = ++conn->reqid;
1082
1083         data.dptr = (uint8_t *)&t;
1084         data.dsize = sizeof(t);
1085
1086         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
1087                                CTDB_CONTROL_TRAVERSE_START, conn->rand_srvid,
1088                                data, NULL, NULL, &cstatus);
1089
1090         if (!NT_STATUS_IS_OK(status) || (cstatus != 0)) {
1091
1092                 DEBUG(0,("ctdbd_control failed: %s, %d\n", nt_errstr(status),
1093                          cstatus));
1094
1095                 if (NT_STATUS_IS_OK(status)) {
1096                         /*
1097                          * We need a mapping here
1098                          */
1099                         status = NT_STATUS_UNSUCCESSFUL;
1100                 }
1101                 goto done;
1102         }
1103
1104         state.fn = fn;
1105         state.private_data = private_data;
1106
1107         while (True) {
1108
1109                 status = NT_STATUS_OK;
1110
1111                 if (packet_handler(conn->pkt, ctdb_req_complete,
1112                                    ctdb_traverse_handler, &state, &status)) {
1113
1114                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1115                                 status = NT_STATUS_OK;
1116                                 break;
1117                         }
1118
1119                         /*
1120                          * There might be more in the queue
1121                          */
1122                         continue;
1123                 }
1124
1125                 if (!NT_STATUS_IS_OK(status)) {
1126                         break;
1127                 }
1128
1129                 status = packet_fd_read_sync(conn->pkt);
1130
1131                 if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1132                         /*
1133                          * There might be more in the queue
1134                          */
1135                         continue;
1136                 }
1137
1138                 if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1139                         status = NT_STATUS_OK;
1140                 }
1141
1142                 if (!NT_STATUS_IS_OK(status)) {
1143                         DEBUG(0, ("packet_fd_read_sync failed: %s\n", nt_errstr(status)));
1144                         cluster_fatal("ctdbd died\n");
1145                 }
1146         }
1147
1148  done:
1149         TALLOC_FREE(conn);
1150         return status;
1151 }
1152
1153 /*
1154  * Register us as a server for a particular tcp connection
1155  */
1156
1157 NTSTATUS ctdbd_register_ips(struct ctdbd_connection *conn,
1158                             const struct sockaddr_in *server,
1159                             const struct sockaddr_in *client,
1160                             void (*release_ip_handler)(const char *ip_addr,
1161                                                        void *private_data),
1162                             void *private_data)
1163 {
1164         struct ctdb_control_tcp p;
1165         TDB_DATA data;
1166         NTSTATUS status;
1167
1168         /*
1169          * Only one connection so far
1170          */
1171         SMB_ASSERT(conn->release_ip_handler == NULL);
1172
1173         /*
1174          * We want to be told about IP releases
1175          */
1176
1177         status = register_with_ctdbd(conn, CTDB_SRVID_RELEASE_IP);
1178         if (!NT_STATUS_IS_OK(status)) {
1179                 return status;
1180         }
1181
1182         p.dest = *server;
1183         p.src = *client;
1184
1185         /*
1186          * inform ctdb of our tcp connection, so if IP takeover happens ctdb
1187          * can send an extra ack to trigger a reset for our client, so it
1188          * immediately reconnects
1189          */
1190         data.dptr = (uint8_t *)&p;
1191         data.dsize = sizeof(p);
1192
1193         return ctdbd_control(conn, CTDB_CURRENT_NODE,
1194                              CTDB_CONTROL_TCP_CLIENT,
1195                              CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL, NULL);
1196 }
1197
1198 /*
1199  * We want to handle reconfigure events
1200  */
1201 NTSTATUS ctdbd_register_reconfigure(struct ctdbd_connection *conn)
1202 {
1203         return register_with_ctdbd(conn, CTDB_SRVID_RECONFIGURE);
1204 }
1205
1206 /*
1207   persstent store. Used when we update a record in a persistent database
1208  */
1209 NTSTATUS ctdbd_persistent_store(struct ctdbd_connection *conn, uint32_t db_id, TDB_DATA key, TDB_DATA data)
1210 {
1211        int cstatus=0;
1212        struct ctdb_rec_data *rec;
1213        TDB_DATA recdata;
1214        size_t length;
1215        NTSTATUS status;
1216
1217        length = offsetof(struct ctdb_rec_data, data) + key.dsize + data.dsize;
1218
1219        rec = (struct ctdb_rec_data *)talloc_size(conn, length);
1220        NT_STATUS_HAVE_NO_MEMORY(rec);
1221
1222        rec->length = length;
1223        rec->reqid  = db_id;
1224        rec->keylen = key.dsize;
1225        rec->datalen= data.dsize;
1226        memcpy(&rec->data[0], key.dptr, key.dsize);
1227        memcpy(&rec->data[key.dsize], data.dptr, data.dsize);
1228
1229        recdata.dptr  = (uint8_t *)rec;
1230        recdata.dsize = length;
1231
1232        status = ctdbd_control(conn, CTDB_CURRENT_NODE,
1233                               CTDB_CONTROL_PERSISTENT_STORE,
1234                               0, recdata, NULL, NULL, &cstatus);
1235        if (cstatus != 0) {
1236                return NT_STATUS_INTERNAL_DB_CORRUPTION;
1237        }
1238        return status;
1239 }
1240
1241
1242 #else
1243
1244 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
1245                                struct ctdbd_connection **pconn)
1246 {
1247         return NT_STATUS_NOT_IMPLEMENTED;
1248 }
1249
1250 #endif